use serde::{Deserialize, Serialize};

use crate::{
    commands::{Command, CommandRequest, RequestParserError, empty_command_response},
    common::types::{SongPosition, Uri},
    request_tokenizer::RequestTokenizer,
};

pub struct Add;

#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub struct AddRequest {
    uri: Uri,
    position: Option<SongPosition>,
}

impl CommandRequest<'_> for AddRequest {
    const COMMAND: &'static str = "add";

    fn into_request_enum(self) -> crate::Request {
        crate::Request::Add(self.uri, self.position)
    }

    fn from_request_enum(request: crate::Request) -> Option<Self> {
        match request {
            crate::Request::Add(uri, position) => Some(AddRequest { uri, position }),
            _ => None,
        }
    }

    fn serialize(&self) -> String {
        match self.position {
            Some(position) => format!("{} {} {}", Self::COMMAND, self.uri, position),
            None => format!("{} {}", Self::COMMAND, self.uri),
        }
    }

    fn parse(mut parts: RequestTokenizer<'_>) -> Result<Self, RequestParserError> {
        let uri = match parts.next() {
            Some(s) => s,
            None => return Err(RequestParserError::UnexpectedEOF),
        };

        let position = match parts.next() {
            Some(s) => Some(
                s.parse::<SongPosition>()
                    .map_err(|_| RequestParserError::SyntaxError(1, s.to_owned()))?,
            ),
            None => None,
        };

        debug_assert!(parts.next().is_none());

        Ok(AddRequest {
            uri: uri.to_string(),
            position,
        })
    }
}

empty_command_response!(Add);

impl Command<'_, '_> for Add {
    type Request = AddRequest;
    type Response = AddResponse;
}